Daniele Marini | Università degli Studi di Milano - State University of Milan (Italy) (original) (raw)

Papers by Daniele Marini

LAP LAMBERT Academic Publishing eBooks, Apr 22, 2012

This book covers multidisciplinary domains. If you are working with colors and electroencephalogr... more This book covers multidisciplinary domains. If you are working with colors and electroencephalographic signals, specially from human brain perception point of view then this book is right for you. We hope that this book will provide you help in designing experimental protocols and related laboratory setup to analyze human brain's response in electroencephalographic signals against colored visual stimuli. This book presents not only the requirements for experimental setups but also covers comprehensive background and introductory information related to human brain, EEG signal processing, suitable tool for pattern recognition along with mathematical models and Brain-Computer Interface applications. We also hope that after reading this book you would be able to recognize colors in EEG signals and will gain the skills in order to utilize colors as visual stimuli in applications for Brain-Computer Interfaces. Please note that this book is resulted as a part of PhD Thesis at University of Milan.

Conference on Colour in Graphics, Imaging, and Vision

In recent years, organic semiconductors have been used to develop a new generation of photodetect... more In recent years, organic semiconductors have been used to develop a new generation of photodetectors; in some cases their outstanding properties, especially in terms of spectral tuning, have been exploited in order to reproduce human cone sensitivities. To date, however, it is still not clear if the spectral differences between real and artificial cone responses, unavoidable at a certain extent, may lead to real, corresponding differences in the final color perception. As a matter of fact, one should note that perception is the final result of a complex analysis and elaboration made by our visual system at a superior level respect to the color sensation, as detected in the retinal photoreceptors layer. Therefore, aiming at the development of an artificial retina, the way how human perception actually works can not be disregarded. In this paper, we focus in detail on the role and effect of spatial normalization, when applied to a set of tristimulus values obtained using different integration curves, derived by different organic semiconducting materials. In a recent work, we proposed an experimental setup to investigate this issue. We used a multispectral rendering of a virtual scene as a simulation of incoming light spectra, and a set of artificial cone sensitivities to obtain different tristimulus values for each combination of integrating curves. Finally, we applied different computational models with and without spatial color computation to partially simulate human perception. A preliminary analysis of the values showed that the application of a spatial color algorithm leads to a normalization of the differences in artificial cones spectral sensitivities. In this paper we present the results of a new session of experiments, based on the same experimental setup, but using new multispectral test images of real scenes, and a different selection of organic active materials. We analyze the values obtained after the application of the processing methods, trying to define some latex in the selection, among the many available organic semiconductors, of their most effective combination. Moreover, we introduce some hypothesis regarding the effect of different frequency cut points and overlapping areas between the photore-sponsivity curves

An emerging problem in IT is how human communication, mediated by computer systems, evolves in ne... more An emerging problem in IT is how human communication, mediated by computer systems, evolves in new and unexpected ways. Diffusion of social networks, virtual reality, videogames, e-learning, mobile communication are changing the way, in particular, teen and young people interact and exchange experience and emotions. To understand and explore the effects on human beings of the new communication paradigms is a challenge that can be tackled by studying it by multiple viewpoints, from perception to high cognitive and psychological levels and recurring to advanced signal processing methods. The availability of low cost EEG recording devices allows us to perform a large amount of experiments, providing the possibility of sound data interpretation, and setting up simulated and real environmental experiment set up. We are less interested in the study of non-elementary perceptual phenomena, rather focused to study interpersonal or human-computer communication processes, by observing brain behaviour through EEG signal analysis. As a matter of fact, visual and auditory perception, still remain the primary means of such communication processes, but higher level brain phenomena are possibly more appealing. Experiments on EEG already demonstrate that not only a visual, motor or auditory stimulus can be detected, but also the imagination of the stimulus itself can also be detected, so opening the road to brain computer interaction. In this paper we will present some preliminary results from experiments on music, colour perception and mono vs. stereo video viewin

2013 6th International IEEE/EMBS Conference on Neural Engineering (NER), 2013

ABSTRACT Steady state visual evoked potentials (SSVEP) are widely used in EEG research as they of... more ABSTRACT Steady state visual evoked potentials (SSVEP) are widely used in EEG research as they offer a relatively high signal to noise ratio allowing the investigation of visual processing at the cortical level. Presentation of a repetitive visual stimulus (flicker, RVS) at a frequency in the range from approximately 1 to 100 Hz, elicits an oscillatory response at the same frequency of the stimulus and/or harmonics which can be observed in the electroencephalogram (EEG), particulary at occipital sites. The frequency and the modulation depth of the RVS determine the strength of the corresponding SSVEP response. While a stronger response allows for a higher signal-to-noise ratio, it does also negatively influence comfort and safety. By relying on visual perception research which characterize the flicker perception thresholds for different frequencies and modulation depths, we focus in this paper on analyzing the SSVEP response near the perception threshold and we show that it is possible to design quasi-imperceptible RVS which elicits a sufficiently strong SSVEP response.

We aim at developing computational methods for the analysis of the signal produced by EEG devices... more We aim at developing computational methods for the analysis of the signal produced by EEG devices in response to simple visual stimuli, to evaluate their impact on perceptual and cognitive processes. In particular, the work is focused on the study and the experimentation of innovative signal processing methods to measure the electroencephalographic answer to specific stimuli. To this aim, we have performed some preliminary experiments collecting EEG data using a Brain-Computer Interface (BCI) device from two groups of users, subjected to simple visual, such as Gestalt images used as stimuli eliciting basic cognitive processes.

Behaviour & Information Technology, 2016

ABSTRACT The experience of immersive virtual reality (VR) can be considered as a communication pr... more ABSTRACT The experience of immersive virtual reality (VR) can be considered as a communication process between human beings, mediated by computer systems, which uses visualisation and other sensory stimulation. In this paper, we analyse how VR characteristics can be explored using semiotic theory and, with methods of generative semiotics, we explore aspects of narrative and interaction in VR. We propose a semiotic analysis of VR communication focusing on syntax, semantics and pragmatics and considering also some principles of generative semiotics. The syntactic level is analysed as determined by the characteristics of the visual communication adopted. The semantic of VR is related to the functional model chosen to realise the virtual system. The pragmatic of VR is based on the human–computer interaction that changes the user's role. We explore how these aspects can be characterised in the context of VR communication design and what principles can be adopted for a VR application, and we present an analysis and a classification of the iconic signs that are being used in VR. Moreover, we present a framework that can be used to classify and describe different kinds of virtual reality systems and to better understand communication in VR, and we use it to classify eight popular systems for e-learning and collaboration.

arXiv (Cornell University), Aug 9, 2022

While Kepler was still working in Graz during 1598, some letters to his mentor Michael Mästlin de... more While Kepler was still working in Graz during 1598, some letters to his mentor Michael Mästlin demonstrate his interest in astronomical clocks and machines. The first letter, dated January 6 th 1598 contains a detailed description of a machine. In the second letter, written between June 1 st and 11 th 1598, Kepler starts with a brief review of clocks and machines of his time, then goes on to describe the requirements necessary for a useful mechanical instrument, based on the latest information of the day. In the Epitome Astronomiae Copernicanae (1618) he reiterates the importance and utility of astronomical and horological machines to divulgate the Copernican model of the Cosmo, to inform and assist scientists in their celestial calculations and hypotheses, even during periods of poor visibility in the night sky. I will present a translation of the Kepler's design and a hypothetical three-dimensional virtual reconstruction of his machine. This project reveals Kepler's ongoing research and understanding of the planets' cinematics, still bound to the homocentric spheres concept while the idea of orbita was maturing. At the same time Kepler's project reveals a reasoning on a clear description of retrograde motion of planets, fully developed later in his Astronomia Nova. His machine demonstrates the Copernican concept of the Sun and its planets as a unique system. He also wants to show how the planet moves from the viewpoint of an Earth based observer. He shows how to solve the basic mechanical problem of moving all the planets simultaneously with just one driving mechanism, which was impossible to accomplish with the Aristotelian theory of homocentric spheres.

Ottagono Rivista Trimestrale Di Architettura Arredamento E Industrial Design, 1996

Journal of Biomedical Engineering and Medical Imaging, 2015

In this paper we have presented results for classification of electroencephalograph (EEG) signals... more In this paper we have presented results for classification of electroencephalograph (EEG) signals produced by the random visual exposure of primary colours i.e. red, green and blue to the subject while sitting in a dark room. Event-related spectral perturbations (ERSP) are used as features for support vector machine (SVM). Our objective was to classify the EEG signals as Red, Green and Blue classes and we have successfully classified the three visual conditions having accuracy of 84%, 89% and 98% with linear, polynomial and radial basis function kernels respectively with in all the groups of data among all the subjects.

Teleoperation: Numerical Simulation and Experimental Validation, 1992

Recent advances in visual simulation and Man Machine Interface methods and tools have given rise ... more Recent advances in visual simulation and Man Machine Interface methods and tools have given rise to a new viewpoint in Human Computer Interaction: Artificial Reality. This viewpoint can be considered as a technical and scientific paradigm, well suited for the implementation of advanced teleoperation systems. In the paper a review of A.R. techniques is presented, with a particular emphasis to aspect relevant for teleoperation.

http://hdl.handle.net/10077/10529 We sought to provide direct evidence of the attention movements... more http://hdl.handle.net/10077/10529 We sought to provide direct evidence of the attention movements during dynamic mental imagery. Observers extrapolated in imagery the horizontal motion of a target with the gaze in central fixation. We recorded the steady-statevisual- evoked potentials (SSVEP) generated by flickering the left and right sides of the screen at two different frequencies. We found a consistent SSVEP modulation as a function of the imagined target position. Concurrent finger pointing, but not mental training, increased the SSVEP modulation. We conclude that the electrophysiological signature of covert visuospatial attention can be used to reveal non-invasively the continuous spatio-temporal dynamics of mental imagery.

International Cultural Heritage Informatics Meeting, 2001

Within the field of cultural heritage restoration, experts are interested in the analysis of data... more Within the field of cultural heritage restoration, experts are interested in the analysis of data describing the condition and history of ancient monuments. Data are usually distributed over many sites. VRML and Java technology, which are well-suited for describing geometrical models and data interaction over the Internet. Unfortunately, the poor quality of VRML real time rendering is a bottleneck for

Our approach to computer simulation of the human movement is based on a high level description of... more Our approach to computer simulation of the human movement is based on a high level description of the grammar of the movement and on the combination of basic movements acquired using motion capture systems. The combinatory techniques inspired by the ancient notation system of the Baroque Dance can lead to achieve complex tasks like synchronisation with the music tempo and rhythm in a simple way. The first phase of our project was the study of the human morphology and possible movements in the Baroque Dance, then we built an anthropomorphic 3D model which articulated structure makes it able to dance. Then we studied the major Baroque Dances, to identify their syntactic structure suitable for a hierarchical decomposition of a complete choreography. Third, we encoded the elementary movements by using a motion capture system with a professional human dancer, building two libraries of simple and complex movements, to be used for the control of the motion of the 3D articulated figure in two dinstict cases: for real-time generated dances and for rendering-based generated dances. Synchronisation with the music tempo and rhythm has also been solved, thanks to the rule that each musical measure corresponds to a complex step, or a word in our metaphor.We implemented two kind of interactive web tools to be used by the choreographer in order to define a choreography for the virtual dancer. The result is an easy to use animation system, settled as an educational application.

In questo articolo presentiamo un approccio quasi-non supervisionato al restauro digitale del col... more In questo articolo presentiamo un approccio quasi-non supervisionato al restauro digitale del colore nei film, ispirato a meccanismi di percezione visiva. Il metodo presentato utilizza uno Spatial Color Algorithm [1] per restaurare l'apparenza del colore piuttosto che il colore fisico. Il lavoro presenta anche due esempi di restauro basati su questo approccio.